If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You may have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.

Awesome work, excellent info. If your off-side sac had a check-valve in the vent line, I bet the other side fill pump would not draw air. This would reduce your fill time and improve the flow rate. yes, a larger intake setup would improve the numbers as it would offer more flow capacity. Down side is, there is a pretty good price increase when you step up from 1" to 1.25". But, a single 1.25" will be less expensive then a pair of 1"

Thru Hull Fitting Advice

Thanks Chad. Been following this because I am adding a pump and two bags to my buddy's 100k boat and there's no talking him into another thru hull. He won't mind the 20% loss, he wasn't even planning on being able to run both pumps at the same time.

that is wicked that you set it up just so we all a had info on what is best for everybody's setup. 2.4 min to me is worth a hole in the boat, only bc I have two small kids and that is 2.4 min shorter that they need to wait. But for some people they may feel that it is not worth it but test is awesome and now people have legit info to make a decision on what set up is best!
Thanks again!

that is wicked that you set it up just so we all a had info on what is best for everybody's setup. 2.4 min to me is worth a hole in the boat, only bc I have two small kids and that is 2.4 min shorter that they need to wait. But for some people they may feel that it is not worth it but test is awesome and now people have legit info to make a decision on what set up is best!
Thanks again!

We have a short season, 2.4 minutes difference may not sound like much but over the entire season that's a lot of time wasted..I'd rather spend it surfing...

The one test that I meant to try out was to run one pump in the forward direction and the other in the reverse direction to see if it forced more water through the filling pump. Maybe that sounds confusing but if you have a T fitting and one pump is emptying and the other is filling then they would both be utilizing the same thru hull fitting. I would think that the pump emptying would increase the line pressure and actually feed the other pump. I am willing to bet that there wouldnt be all that much of a difference because they should be moving the same amount of water.

I am also a little nervous about the one pump that is emptying injecting air into the system and causing the flow to go to hell. I am thinking that I'm going to go with a thru hull fitting for each pump myself. Its the air issue that I am afraid of all the way around.

The one test that I meant to try out was to run one pump in the forward direction and the other in the reverse direction to see if it forced more water through the filling pump. Maybe that sounds confusing but if you have a T fitting and one pump is emptying and the other is filling then they would both be utilizing the same thru hull fitting. I would think that the pump emptying would increase the line pressure and actually feed the other pump. I am willing to bet that there wouldnt be all that much of a difference because they should be moving the same amount of water.

I am also a little nervous about the one pump that is emptying injecting air into the system and causing the flow to go to hell. I am thinking that I'm going to go with a thru hull fitting for each pump myself. Its the air issue that I am afraid of all the way around.